package com.edu.boot.common;


import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**
 * @author zsj
 * 2019-08-20
 */
public class MD5Utils {
    /**
     * 使用md5的算法进行加密
     */
    public static String md5(String plainText) {
        byte[] secretBytes = null;
        try {
            secretBytes = MessageDigest.getInstance("md5").digest(plainText.getBytes());
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException("没有md5这个算法！");
        }
        // 16进制数字
        String md5code = new BigInteger(1, secretBytes).toString(16);
        // 如果生成数字未满32位，需要前面补0
        for (int i = 0; i < 32 - md5code.length(); i++) {
            md5code = "0" + md5code;
        }
        return md5code;
    }




    /**
     * 可逆的的加密解密方法；两次是解密，一次是加密
     * @param inStr
     * @return
     */
    public static String md5Minus(String inStr){

        char[] a = inStr.toCharArray();
        for (int i = 0; i < a.length; i++){
            a[i] = (char) (a[i] ^ 't');
        }
        String s = new String(a);
        return s;

    }

    // fdgdfgvsdfgs5e5a3c75d4e1
    public static void main(String[] args) {
        System.out.println(md5("E10ADC3949BA59ABBE56E057F20F883E"));
    }
}

